Central Building Research Institute, Roorkee (U.P.).
Deposition of sand in casing pipes, commonly known as sand boiling, is caused by two main processes: (i) advancement of a sand column from the base of the bore-hole with seeping water and (ii) sedimentation of sand from the sand slurry formed by boring operations. The degree of sand deposition is a function of the fineness of the particles. While bentonite slurry has been widely found satisfactory in progressing uncased bore-hole in sandy soils, the study detailed in this article indicates that it can also be satisfactorily used to prevent sand boiling or sand deposition in bore-holes using casing pipes leading to reliable sub-soil exploration, in situ testing and sampling of sands.
